I've been having a problem with PT12HD on my system in my sig. It will happen at least 4 or 5 times a day when working with PT12. I've been working with Studio One V2 and V3 for the last 3 weeks and no problems there using UAD plugins.

The system is pretty new. It's a fresh install, no ver. 10 or rtas on the machine. The session is only using UAD DSP and Avid native plugs. The problem has happened with other sessions, but on this one I was able to recover, sort of, by hitting Command and F1 and F2. Before I couldn't get to the force quit and had to shut off the machine with the hard switch.

The problem shows up as everything is playing back just fine, and then the audio gets a 'hiccup' and the machine continues to play the audio to the end. However the gui is frozen and none of the keyboard commands work... Spacebar to stop, etc. and the spinning beachball of death shows when you move the cursor off the Pro Tools gui.

Just before when this happened I started hitting command keys and when I got to the Command+F2, the screen went black, then I hit it again and it came back and the gui was working...sort of. The meters were not frozen, but they were updating only about every 1 second or so. So were the Pro Tools gui buttons. I opened the console and copied all the messages to a log and there were many regarding this. The most notable being:

I was getting problems like this in PT12 for a while. But then it went further to a problem where every time I Bounced a mix it would create a state where all tracks played back through the main output at full level regardless of muting or routing.

I have reverted to PT11 so I can still function, but like you, I also have a new Mac Pro and a clean Yosemite system that never had PT10 on it. I thought maybe it was a hardware problem, but I find it interesting to read that someone else with a new system is having similar issues with PT12 and Yosemite.

I was getting problems like this in PT12 for a while. But then it went further to a problem where every time I Bounced a mix it would create a state where all tracks played back through the main output at full level regardless of muting or routing.

I have reverted to PT11 so I can still function, but like you, I also have a new Mac Pro and a clean Yosemite system that never had PT10 on it. I thought maybe it was a hardware problem, but I find it interesting to read that someone else with a new system is having similar issues with PT12 and Yosemite.

Thanks for responding Sonny. It would be interesting if you had the console reports from the time you had the issue. Comparing them might give a clue. I did notice that OSX was reporting that it was expecting Pro Tools to return 10.10.2 but got 10.9.8 instead. At least it thought it important enough to write it to the log. If that is valid, does it mean that PT12HD is only qualified, or should I say 'versioned' only as far as Mavericks?

My system shipped with 10.10.2, so I can't really go back...not without finding an old version of Mavericks, blowing away my drive and starting over...I'm not interested in going through a weeks worth of work just to find that PT11HD is just a flaky.

I would like to be running Mavericks. It's scarey out here on the 'bleeding edge', but Yosemite has been out long enough that the beta of 'El Capitan' has been released...

Very interesting.
I got this problem a few weeks ago and I still don´t know what it is.
I found this thread cause I was searching for this line: 29.07.15 14:55:44,392 WindowServer[163]: disable_update_timeout: UI updates were forcibly disabled by application "Pro Tools" for over 1.00 seconds. Server has re-enabled them.

Every ten minutes (or so) I have a few of these lines in the console but it doesn´t freeze there.

I tried everything what one normally would do in such a case: No plugins, no external devices, repair permission, a.s.o.

I have several installations with 10.10.3 / 10.10.4 and 11.3.1 / 12.1.
In any combination it crashed.
Right today I did a super clean install of 10.10.4 and 11.3.1.
Nothing else. No further plugins no other apps.

Right now 3h without a problem.
I will see if it´s still running tomorrow morning.

Very interesting.
I got this problem a few weeks ago and I still don´t know what it is.
I found this thread cause I was searching for this line: 29.07.15 14:55:44,392 WindowServer[163]: disable_update_timeout: UI updates were forcibly disabled by application "Pro Tools" for over 1.00 seconds. Server has re-enabled them.

Every ten minutes (or so) I have a few of these lines in the console but it doesn´t freeze there.

I tried everything what one normally would do in such a case: No plugins, no external devices, repair permission, a.s.o.

I have several installations with 10.10.3 / 10.10.4 and 11.3.1 / 12.1.
In any combination it crashed.
Right today I did a super clean install of 10.10.4 and 11.3.1.
Nothing else. No further plugins no other apps.

Right now 3h without a problem.
I will see if it´s still running tomorrow morning.